1. Technical Field
This invention relates to a device for levelling and aligning surface covering parts, appropriate to install a surface of ceramic parts or similar that are suitably levelled and aligned.
The invention is applicable in the field of construction and refurbishment, particularly in the application of surface covering tiles or parts.
2. Description of the Related Art
There currently exist in the market different devices designed to facilitate the levelling and alignment of surface covering parts using a layer of mortar, glue cement or other suitable adhesive for securing them to the surface in question.
The purpose of these known devices is to facilitate the correct positioning of the parts forming the covering, so that the covering defines a flat, levelled surface, and the parts in question are kept at uniform distance apart.
A known device is described in the U.S. Pat. No. 4,397,125, which has a rear plate with a hole in which a screw or protruding tab is fixed directly with fixing means to said screw. Said device also has a front clamping plate mounted on it, which is forced against the rear plate by a wing nut or similar, in order to trap the covering parts by their edges. The device in this patent has a number of drawbacks, notably that the threaded parts of the screw and/or wing nut may be rendered useless if they come into contact with the mortar or fixing material for the covering parts, and the excessively large separation between said parts because of the thickness of the screw, especially when the parts to be used are of small dimensions.
The document U.S. Pat. No. 5,675,942 describes an aligning and spacing device for wall panels which comprises a base plate with an attachment or locking stem, locking plate and lock which keep the front and rear sides of a pair of panels laterally aligned with a surface while the securing product for said panels dries.
The lock incorporated in the locking plate is coupled to the stem using complementary gear teeth of sizeable dimensions, which means that there is an excessive length between the successive holding points and that the alignment and levelling of the parts forming the covering is not sufficiently precise.
Other known devices are described, for example, in patent documents US 2006/0185269 and US 2006/0185319, which have a top plate with an array of spacer fins and a bottom plate, in which the plates are joined by a stem or attachment which extends from the bottom plate through the top plate. This stem has a number of notches for lateral mounting of a metal insert to hold the top plate in position.
As in the previous case, these inventions do not allow progressive insertion and appropriate adjustment of the top plate during the levelling of the parts which form the covering.
The Spanish utility model ES 1070518 U describes a levelling device for the positioning of covering parts which comprises a flat lower body from which a flexible attachment emerges from above for placing between the covering parts and a second upper body with a through hole for adjustable mounting on the flexible attachment. Said flexible attachment has a rectangular cross-section and, on its larger faces, two opposing gear teeth whose teeth are offset lengthwise. The through hole of the second body comprises two opposing ratchets which mesh in an alternate manner with the teeth corresponding to the two sides of the flexible attachment, providing a greater number of fixing points than in the abovementioned inventions.
This invention, like the previous ones, has the disadvantage that each device is positioned individually, which makes alignment and levelling of covering parts difficult, especially when they are of longer length. Another drawback in use comes from the fact that a large number of individual, independent devices must be used for the alignment and levelling of the covering parts.
Another drawback of this device is determined precisely by the flat configuration of the lower body, which prevents the covering parts from being gripped correctly in the cement or fixing medium with regard to the surface to be covered.